The Thirsties Diaper Cover is just wonderful!  I love that there are so many beautiful colors to choose from.  The double leg gusset is perfect for holding in breast-fed poo, and we have never had a leak while using these.  The cut of these covers is generous enough for a prefold with a doubler, and also lots of different fitted diapers, too.  The sizing is wonderful!  We used the X-Small sized cover starting when our son was about nine pounds and it fit him perfectly.  We have occasionally had a pee leak using these, mostly nap time when the waistband of baby's pants slipped under the top...